81 results about "Atmospheric models" patented technology

A format for providing messages among GNSS apparatus includes providing a message identification block and a message body. The message identification block includes information specifying a message length and a message type block specifying a message type. Rather than sending all data from one apparatus to another, ambiguous observation data is sent to conserve bandwidth. At the sender a deconstruction of GNSS code and carrier observations using knowledge of the signal structure and constellation geometry, together with simplifications of atmospheric models, allows removal from the observation data of that information which can be implicitly understood or recreated by the recipient. This enables only the necessary information to be packed for transmission to the recipient.

The invention relates to a time and location dependent atmosphere model and especially determining the altitude of a mobile terminal based on this model and the measured barometric pressure at the location of the terminal. The atmosphere model provides a long term, wide area barometric pressure model estimate.

The invention relates to a satellite starlight refraction navigation error determination and compensation method. The method comprises the following steps: firstly, generating data of a satellite orbit by virtue of STK software; establishing a satellite attitude planning model; determining an actual observation visual field, and simulating an observation star map comprising refraction stars and non-refraction stars; calculating to obtain the tangential height h of the refraction stars; calculating to obtain the tangential height h'' of the refraction stars with errors of refraction angles and errors of an atmospheric model, wherein tangential height errors are mainly caused by the measurement precision errors of the refraction angles and the errors of the atmospheric model; calculating to obtain the position of a satellite under a geocentric inertial coordinate system; and performing filtration by an extended Kalman filtration method, and outputting a starlight refraction navigation estimated position and position errors. The method provided by the invention can realize accurate prediction of navigation precision of a satellite starlight refraction navigation system, and is comprehensive in error analysis and accurate and reliable in results.

Characterizing atmospheric conditions is accomplished by measuring at least one varying spectral characteristic of sound at a plurality of intervals from a sound source with the point of measurement and the sound source in relative motion and separated by altitude. The spectral characteristic of the sound at each interval is attributed to a path traveled by the sound and a plurality of simultaneous equations is created for the plurality of paths using a second plurality of altitude segments for each path, each segment having a particular vector as a variable on the spectral characteristic, the initial coefficients in each vector assumed based on predetermined atmospheric models for each altitude segment. The resulting calculated vector and the predetermined atmospheric model are iterated for a minimized cost function in a variational analysis to determine the vector for each altitude segment, the vector providing atmospheric properties for the associated altitude segment.

The invention discloses a method for controlling glide flying ballistic curve damping. The method comprises the following three major steps: step 1: taking into consideration influence of earth curvature, ignoring influence of earth rotation, studying three degree-of-freedom kinematical equation of gliding of an aircraft, and acquiring condition of furthest distance of powerless gliding of the aircraft; step 2: based on the atmosphere model and the aircraft aerodynamic force model already known, performing force analysis on the longitudinal plane of the aircraft under stable gliding condition, and acquiring stable gliding ballistic curve angle of inclination gamma*; step 3: adding feedback to the control instruction, introducing ballistic curve damping control. The method is a guidance method enabling stable gliding of the aircraft, and is applicable to aircrafts having a glide ballistic curve, including a cannonball of a low speed and a short range as well as a long-distance, reentry, and hypersonic-velocity aircraft.

The invention discloses an on-line parameter identification method for jumping type reentry of a lunar spacecraft. The on-line parameter identification method comprises the steps of obtaining on-line estimation values of an atmospheric density scaling factor and a lift-drag ratio scaling factor through a low-pass filter at a primary reentry descending branch, executing track forecasting, correcting the deflection of a drop point, and constructing a fitting function relation between the atmospheric density scaling factor and the height; obtaining an atmospheric density scaling factor at a primary reentry ascending branch and in the initial stage of a secondary reentry branch via a constructed fitting function, estimating a lift-drag ratio scaling factor of the lunar spacecraft on line, executing track forecasting, and correcting the deflection of the drop point; estimating an atmospheric density scaling factor and a lift-drag ratio scaling factor in the later stage of the secondary reentry branch, executing track forecasting, and correcting the deflection of the drop point. According to the on-line parameter identification method, the robustness and the precision of a guidance algorithm are improved; the adaptability to a real atmosphere model is high.

The invention discloses an inversion method for the laser transmittance of the whole atmosphere. The method comprises the following steps of: measuring an aerosol optical depth of the whole atmosphere by selecting a specific wavelength, and performing inversion to obtain the aerosol optical depth of the whole atmosphere of other wavelengths; and inverting the transmittance of the whole atmosphere. The method has the advantages that: inversion of the transmittance of the whole atmosphere in ultraviolet, visible and infrared bands is realized by using a multi-band solar radiometer and atmospheric model or local atmospheric measured data and high-resolution atmospheric absorption optical depth computation software; and the problem about measurement of the laser transmittance of the whole atmosphere in a broad spectrum is solved.

The invention discloses a regression model-based fast single-image defogging algorithm and system. The algorithm includes a training process of a regression model and a processing process of a foggy image. The training process includes the following steps that: a fog-free image block is generated and is adopted as a sample; an atmospheric model is utilized to add fog to the sample; the sample feature value of the sample is extracted; and an SVM learning regression model is utilized according to the sample feature value. The processing process includes the following steps that: a foggy image is inputted, the foggy image is divided into a plurality of uniform blocks, and the maximum channel image of the foggy image is extracted; image block feature extraction is performed on the uniform blocks, and transmission parameters are estimated according to the SVM learning regression model, and guided filtering is adopted to optimize a transmission diagram; maximum value filtering and median filtering are performed on the extracted maximum channel image, guided filtering is adopted to optimize atmospheric light; and inverse transformation is carried out according to the filtering optimized transmission diagram and the optimized atmospheric light, so that a clear image can be obtained. With the algorithm adopted, fog removing processing can be performed on an image fast and accurately, and image processing quality can be effectively improved.

The invention discloses an integrated space and terrestrial information based stereoscopic monitoring method for air pollution and a monitoring system. The method comprises the following steps: establishing satellite remote sensing and atmospheric model monitoring to monitor the distribution and diffusion trends of large-scale dyes in a region to initially determine local and external sources; establishing a laser radar network monitoring system to locate and track air pollution sources at the same time; and establishing a densely distributed ground monitoring grid site for accurate analysis of the causes of atmospheric pollution sources. Through the three-level monitoring system, the detection of air pollution in the monitoring area can be completed, and serious areas of air pollution, sources of pollutants, and the distribution and diffusion situation of key pollution sources can be clarified. And then the processing, statistics, and analysis of massive data can be completed based ona software platform to obtain monitoring results. The invention can realize effective monitoring of atmospheric pollutants, which has high distance resolution and time resolution.

A calibration system for an infrared imaging system includes an infrared sensor having a sensor model for imaging a target having a target spectral signature. The infrared imaging system includes an atmospheric model having atmospheric spectral values. The calibration system comprises a blackbody calibration source having a calibration source spectral signature and a computer for receiving the sensor model, the target spectral signature, the calibration source spectral signature and the atmospheric spectral values. The computer predicts a target spectral signature propagation at the infrared sensor and matches the target spectral signature propagation with the calibration source spectral signature propagation to determine a blackbody calibration source temperature for radiometric calibration of the infrared sensor.

Methods and systems for the design and execution of an aerospace or aeronautic system are provided. The aerospace or aeronautic system may incorporate planetary environment models and models of equations of motion. The planetary environment models mathematically represent planetary environment specifications, such as atmosphere and wind. Atmosphere models include standard day atmosphere models and non-standard day atmosphere models, and wind models include continuous wind turbulence models and discrete wind turbulence models. The models of equations of motion include models of three-degree-of-freedom equations of motion with variable mass and models for six-degree-of-freedom equations of motion with variable mass. As a result, the present invention can design and execute a target system more accurately than the conventional system that provides only standard day planetary environment models, continuous wind turbulence models, or fixed mass equations of motion models.

The invention relates to a water resource scheduling method based on land-atmosphere coupling, and the method comprises the following steps: 1, carrying out the rainfall forecast according to a numerical atmospheric model WRF; 2, setting the parameters of a Hebei rainfall flood model; 3, carrying out the rainfall forecast, and driving the Hebei rainfall flood model to carry out the radial flow forecast; 4, determining a water resource scheduling scheme based on the radial flow forecast. Starting from the improvement of the radial flow forecast precision and the prolonging of the radial flow forecast period, the invention provides the method. The method can provide sufficient time for a decision maker to make a water resource scheduling scheme, can judge the water storage and discharge amount of a reservoir more precisely, makes the most of limited water resources, gives the fullest play to the benefits of water supply, is especially suitable for a north region which is the most affected by the activities of human beings, can achieve the rolling forecast of rainfall and radial flow through combining with weather forecast, provides a reasonable water resource scheduling basis for a water department, and is very universal.

A method for inversing surface temperature and emissivity from a remote sensing MODIS data comprises the steps of forward simulating by utilizing an atmospheric radiation transferring simulation software MODTRAN4 aiming at the atmospheric model, the region and the season of the 29th, 31st and 32nd thermal infrared bands of the received remote sensing MODIS data to create a training and testing database, retraining and retesting the training and testing database by using a neural network, back calculating an actual MODIS image data, verifying the actual ground surface and analyzing the application. The surface temperature and the emissivity received by the invention have the advantages of high precision, wide application range and simple operation.

The invention discloses an atmospheric correction method and system. Wherein, the method includes: acquiring data from the WFV camera of the Gaofen-1 satellite; calculating the apparent reflectance of each band pixel of the WFV camera according to the data; using the radiation transfer mode and the WFV camera’s Correlation calculations are performed on the band response function, and the correction of the scattering difference of atmospheric molecules in different regions on the WFV camera remote sensing image is completed, and the corrected atmospheric parameters are obtained, thereby forming an atmospheric parameter lookup table; and according to the apparent reflectance and the atmospheric parameter lookup table Obtain the surface reflectance of each band pixel of the WFV camera to achieve atmospheric correction. The invention implements atmospheric correction based on the data of the WFV camera of the Gaofen-1 satellite, can quickly and conveniently obtain real surface reflectance, and provides a data source for quantitative applications.

The invention discloses an atmospheric boundary layer detection method based on a hybrid laser radar. The basic principle is that the hybrid laser radar is used, a direct detection aerosol laser radarsystem and a coherent wind-measuring laser radar system are integrated, the vertical profiles of aerosol optical characteristics and turbulence intensity are simultaneously detected the atmospheric boundary layer heights are separately inverted, and various types of atmospheric boundary layers are judged by comparing the difference between the heights with a selected threshold value. The atmospheric boundary layers can be quantitatively classified with only one device, and various types of boundary layers can be quantitatively parameterized, the atmospheric boundary layer detection method based on the hybrid laser radar is helpful to further improve the accuracy of atmospheric models such as climate models, weather forecast models and atmospheric pollution diffusion models.

The present invention relates to a typical rainfall event selection method for a numerical atmospheric model. The method comprises: a typical rainfall event classification method based on individual rainfall amount; a rainfall time inhomogeneity calculation method; a rainfall spatial inhomogeneity calculation method; and a typical rainfall event selection method based on a rainfall spatial-temporal inhomogeneity coefficient. In the invention, the standardized typical rainfall event selection method is provided for selection and adjustment of a numerical atmospheric model from the perspective of rainfall amount and spatial-temporal distribution, the rainfall type is quantitatively described, and the simulation accuracy of the numerical atmospheric model for different types of rainfall in a certain research area is measured, which can not only provide the basis for model setting in the research area, but also shows that the model is more suitable for which type of rainfall, provides the basis for model selection and provides reasonable numerical atmospheric model simulation plans with respect to different types of rainfall for relevant departments such as meteorology, water conservancy and the like. The typical rainfall event selection method of the invention can be widely applied.

The invention provides a short-time atmosphere model modification method based on measured atmospheric density. The method comprises the following steps: selecting an atmosphere density model, and collecting and calculating measured atmospheric density in a set duration; respectively performing linear fitting on the density value of the atmosphere model and the measured density value so as to obtain a measured atmospheric density fitted curve and a model density fitted curve; calculating an included angle between the measured atmospheric density fitted curve and the model density fitted curve; and rotating the model density fitted curve point by point, thereby obtaining a time value t' after rotation and a selected atmosphere model density value after rotation. According to the method disclosed by the invention, the measured atmospheric density value is introduced into orbit calculation, and the spacecraft orbit forecast accuracy is well improved.

The invention provides an underwater image enhancement method and an underwater image enhancement device, which can improve the restoration accuracy and efficiency of an underwater image. The method comprises the steps that an underwater original image is acquired, and an underwater optical imaging model is established according to underwater imaging characteristics; a characteristic that an underwater optical imaging model is similar to an atmosphere model is utilized, a dark channel prior defogging algorithm for performing linear programming on transmissivity is utilized to perform clearnessprocessing on an underwater original image to obtain a first clear image, and the clearness processing comprises contrast enhancement; performing color correction on the underwater original image byusing a gray world algorithm to obtain a second clear image; and fusing the first clear image and the second clear image by using an image fusion algorithm based on wavelet transform to obtain an underwater restored image. The invention relates to the technical field of image enhancement and restoration.

The invention provides a measuring method of outdoor typical ground feature pBRDF (Polarization bidirectional reflection distribution function) under different weather conditions. The method comprisesthe following steps of under the unblocked conditions, obtaining polarization information of a typical ground feature by using a polarization imaging detection system; under the condition of completing blocking the direct sun light, obtaining the polarization information again by using the polarization imaging detection system; subtracting the polarization information of the typical ground feature measured in the two times to obtain the polarization light Stokes vector obtained by the ground feature reflection direct sun light and the sky scattering light; respectively measuring the distancebetween a blocking article and the detection system and the posture and the size of the shielding article; measuring the aerosol optical thickness and the ground direct radiation degree by using a heliograph; selecting an atmosphere model parameter by combining the local weather conditions; inputting the atmosphere model parameter into a radiation transmission model to obtain sky scattering lightpolarization information; selecting the proper typical ground feature parameter model; combining the blocking article position to calculate the Stokes vector of the blocked part generated by the ground feature reflecting sky scattering light; subtracting the part caused by the sky scattering light from the measured Stokes vector; finally, through the comparison to a standard plate, solving the typical ground feature surface real pBRDF value. The influence of the sky scattering light on the measurement of the typical ground feature pBRDF value measurement is obviously reduced; the measurement precision of the outdoor typical ground feature pBRDF in complicated weather is improved.

The invention relates to a high-resolution historical rainfall retrieval method based on a mesoscale numerical atmospheric model and high resolution, which comprises the following steps of: determining the resolution of rainfall data, rainfall output of the mesoscale numerical atmospheric model, dividing a control unit, calculating a correction coefficient and correcting rainfall data. Through themodification scheme of the invention, on the one hand, the resolution information of the rainfall output data of the mesoscale numerical atmospheric model in space is reserved, and the spatial distribution law of rainfall is reflected. On the other hand, the control area of each rainfall station is divided by Tyson polygon method. The grid within the control area of a rainfall station belongs tothe rainfall station, and the simulated grid rainfall is corrected by the measured rainfall information of the rainfall station. From the initial time of rainfall, the surface rainfall at each time isbased on the measured data of rainfall station, and the mesoscale numerical atmospheric model is used to output the rainfall space proportional distribution to different size grids, which can ensurethat the surface rainfall on each control surface is equal to the measured rainfall.